i2c: qup: Fix pm_runtime_get_sync usage

This patch corrects the error check on the call to pm_runtime_get_sync.

Signed-off-by: Andy Gross <agross@codeaurora.org>
Reviewed-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>